VIJAYAWADA: In what is termed a major milestone, the water resources officials on Friday initiated the diversion of water to Godavari delta region via the river sluices of Polavaram Irrigation Project by enabling the flow via approach channel, spill channel and pilot channel for the first time. The water is expected to reach Sir Arthur Cotton Barrage at Dowleswaram in three days. It will be made available to the delta from June 15 as promised earlier, the officials said.
The process began with the removal of the temporary bund at the approach channel to divert water from the river. With the closure of gaps in the upstream cofferdam, which is being raised to the desired height to enable the construction of the earth-cum-rock fill dam, the flow of the flood is obstructed and the water level rises naturally. Thereon, it is diverted into the pilot channel via approach channel and spill channel before it reunites with the river’s natural course. This entire diversion is about 6.6 km — 2.4 km long approach channel, 3.1 km spill channel and 1.1 km pilot channel, which is a rare engineering feat, the officials said.
“The diversion of water via river sluices is nothing short of ‘Bhagiratha Prayatnam’ as we are diverting a perennial river with an average flood of 26 to 36 lakh cusecs. On Chief Minister YS Jagan Mohan Reddy’s direction and under the guidance of Water Resources Minister P Anil Kumar, Chief Secretary Aditya Nath Das and Secretary J Syamala Rao, we have started diversion of water via the approach channel-spill channel-pilot channel route. There are 10 river sluices and we can divert 1,000 cusecs from each of them.
This way, we can divert 1 TMC of water per day. If water in the river increases to 25.72 TMC, we will operate the radial gates to let it downstream,” explained Engineer-in-Chief C Narayana Reddy.Chief Engineer (PIP headworks) B Sudhakar Babu noted that the water is expected to reach Dowleswaram Barrage, which is about 42-45 km away, in three days. Minister Anil Kumar participated in the programme via virtual link.
Project executing agency Megha Engineering and Infrastructures Ltd (MEIL), which completed the works in a record time, stated that projects in East and West Godavari districts such as Tadipudi, Pattiseema and Pushkaram lift irrigation schemes will also receive water through the approach channel from now for drinking and irrigation. The agency explained that the approach channel was excavated to the extent of 2.4 km, thereby forming a way for the river diversion. About 55 lakh cubic metres of earth excavation work has been done and another 4.88 lakh cubic metres of work has to be completed.
“Out of total 5.92 crore cubic metres of earth work, till now 5.24 crore cubic metres of work has been completed. Out of 17 lakh cubic metres of work related to CC slabs of spillway, 15.17 lakh cubic metres of work has been completed. Hydraulic gates are also arranged. As part of this, 22 power packs have been installed at 44 gates and 28 radial gates have been raised hydraulically so that water can be released in case of floods. Till now 76.29 per cent of headworks has been completed,” MEIL said.
MEIL associate vice-president Rangarajan said despite several odds, including floods last year and Covid-19 imposed crisis, the agency reached the target as set by the government within stipulated time. He added that the construction of Polavaram project would also be completed as per schedule to release water for Kharif-2022.